We have seasons.
There were two theories posed:A1: The distance from the sun gives us seasons.
A2: The tilt of the earth gives us seasons.
Both theories have merit since they satisfy at least half of the criteria for a scientific theory.
Both theories could explain the initial observation. A1 assumes that the closer we are to the sun, the warmer we will be and the more likely it will be summer. A2 is based on the idea that more direct sunlight will make us warmer and make it more likely to be summer.
D1: When it is Summer in the North it is Winter in the South.
D2: The Earth is closest to the Sun on about January 4 of each year (winter in the U.S.)
D3: Summers correspond to times when the rays of the Sun strike the ground more directly.
Distance Tilt North/South Winters no yes U.S. Winter When Closest no no Direct Rays no yes
From this data (distance - 0, tilt - 2), it would seem that the seasons are due to the tilt of the earth's axis.
(One reference: http://csep10.phys.utk.edu/astr161/lect/time/seasons.html)
Here is the paper that follows from the abduction "outline" above.
If both the distance from the sun theory and the tilt of the earth's axis theory have merit as scientific theories for seasons and the tilt of the earth's axis theory leads us to expect more data than the distance from the sun theory, then seasons are most likely due to the tilt of the earth's axis. Both the distance from the sun theory and the tilt of the earth's axis theory have merit as scientific theories for seasons and the tilt of the earth's axis theory leads us to expect more data than the distance theory. Therefore, seasons are most likely due to the tilt of the earth's axis.
The criteria for a scientific theory to have merit is that the theory satisfy at least half of the conditions of a good theory. This is a good practice since it would require a theory to pass at least half of the conditions, but would keep some theories where there was still some doubt as to the merit of the theory and would allow for a variety of theories to be considered. It also seems reasonable to require any theory that is chosen as the best theory to meet at least this basic criteria. Looking at the data surrounding an observation and deciding if the data is likely given a particular theory is an established method of evaluating theories. The more data that is likely for a given theory, the more confidence we would have that the theory under consideration correctly explains the observation. It makes sense then that when two competing theories exist the one that finds the most data likely is the better theory. These statements support the idea that "If both the distance from the sun theory and the tilt of the earth's axis theory have merit as scientific theories for seasons and the tilt of the earth's axis theory leads us to expect more data than the distance theory, then seasons are most likely due to the tilt of the earth's axis."
It is well known that being close to a source of heat makes you hotter than being farther away from the source of heat. The distance from the sun theory states that when we are closer to the sun we should experience summer and when we are farther from the sun we should experience winter. It is also well known that the earth travels in an elliptical orbit and the distance from the sun does vary. The distance from the sun theory could then account for the seasons. If the distance from the sun theory satisfies more than half of the criteria for a scientific theory, then the distance from the sun theory has merit as a scientific theory. The distance from the sun theory is not complicated and has no inconsistencies. No fundamental principles are violated by this theory. This theory is consistent with the initial observation. The theory applies to the area of investigation and does not go far beyond. A competent, well-known researcher put forward the theory. The proposer was aware of other theories and disclosed all methods. The math used is appropriate. No outside agenda is known. These statements suggest that the distance from the sun theory satisfies eight out of eight of the criteria, which is more than half of the criteria for a scientific theory. Therefore, the distance from the sun theory has merit as a scientific theory.
It is well known that getting direct sunlight makes you hotter than indirect sunlight. The tilt of the earth's axis theory states that when the sun's rays directly hit the earth we should experience summer and when the sun's rays indirectly hit the earth we should experience winter. It is also well known that the earth spins on an axis that is tilted, causing the top of the earth to receive more direct sunlight than the bottom of the earth during part of the orbit around the sun and that the opposite is true during other parts of the orbit. The tilt of the earth's axis theory could then account for the seasons. If the tilt of the earth's axis theory satisfies more than half of the criteria for a scientific theory, then the tilt of the earth's axis theory has merit as a scientific theory. The tilt of the earth's axis theory is not complicated and has no inconsistencies. No fundamental principles are violated by this theory. This theory is consistent with the initial observation. The theory applies to the area of investigation and does not go far beyond. A competent, well-known researcher put forward the theory. The proposer was aware of other theories and disclosed all methods. The math used is appropriate. No outside agenda is known. These statements suggest that the tilt of the earth's axis satisfies eight out of eight of the criteria, which is more than half of the criteria for a scientific theory. Therefore, the tilt of the earth's axis has merit as a scientific theory.
When it is Summer in the North it is Winter in the South. This is likely given the tilt of the earth's axis theory (direct sunlight in the north and indirect sunlight in the south), but would not be likely given the distance from the sun theory (both should have the same season since it only depends on distance).
The Earth is closest to the Sun on about January 4 of each year (winter in the U.S.). It is not likely that it would be winter when the earth is closest to the sun given the distance from the earth theory. The tilt of the earth's axis theory has nothing to say about this observation (it isn't likely given this theory either).
Summers correspond to times when the rays of the Sun strike the ground more directly. This observation is likely given the tilt of the earth's axis theory, but not addresed by the distance from the sun theory (again not likely) .
This analysis suggests that there are two pieces of data likely given the earth's axis theory and zero pieces of data likely given the distance from the sun theory. If both the distance from the sun theory and the tilt of the earth's axis theory have merit as scientific theories for seasons and the tilt of the earth's axis theory leads us to expect more data than the distance theory, then seasons are most likely due to the tilt of the earth's axis. Both the distance from the sun theory and the tilt of the earth's axis theory have merit as scientific theories for seasons and the tilt of the earth's axis theory leads us to expect more data than the distance theory. Therefore, seasons are most likely due to the tilt of the earth's axis.